Conventionally, silica-based coating films have been widely used as planarized films and interlayer insulating films within semiconductor elements such as LSI (large-scale integration) elements. These types of silica-based coating films are formed by chemical vapor deposition methods (CVD methods) and spin coating methods and the like. Because of their simplicity, methods in which the silica-based coating film is formed using a spin coating method are particularly widely employed.
Demands for ever greater integration of the above semiconductor elements such as LSI elements continue to grow. However, this increased integration leads to increasingly finer wiring, which results in increased wiring capacity that can cause problems of longer signal delay times. In order to address these types of problems, materials capable of forming silica-based coating films with lower dielectric constants are required.
In order to achieve this type of reduction in the dielectric constant, patent reference 1 discloses the addition of a thermally decomposable, volatile organic polymer for the purpose of pore formation, thereby converting the formed silica-based coating film to a porous state.
[Patent Reference 1]
Japanese Unexamined Patent Application, First Publication No. 2002-201415